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Soil cutting for preparing a proper seedbed with the purpose of crop production is tillage. Though tillage is a dynamic process, most of the previous studies are based on quasi-static analysis following the passive earth pressure theories. The focus of this research was to describe the mechanical behavior of soil under the action of a tillage tool from the dynamic perspective using fluid flow analysis. This paper describes the application of a commercially available, three-dimensional computational fluid dynamics (CFD) model to simulate and analyze dynamic tool interaction with soil during tillage. Soil has been considered as a Bingham material taking into account its non-Newtonian viscoplastic behavior. Simulations used a rectangular flow geometry based on the tool influence zone obtained from previous research. Soil flow behavior has been studied as a conduit with the interaction of a bluff body in the flow domain.

Several mechanical demining machines employ flails as the key mechanism for neutralizing landmines. Typically, flail systems consist of a rotating drum with a series of long chains with masses attached at the end. These masses strike and mill the ground that detonates and/or fragment buried landmines. Despite flail-based technology existing for several years in the demining field, minimal studies regarding the interaction with soil have been conducted. Three chain flail systems were evaluated in the soil bin at various rotational speeds. High speed videography of single pass operations indicated that a consistent and repeatable cleared path was not obtainable. This validated the need for multiple passes to effectively clear a minefield. The results were compared with the Mine Hammer mechanism that had consistent impacts on the surface. The load distribution at the various depths was recorded and the magnitude of the impulses calculated varied with depth and level of soil compaction.

An antipersonnel landmine neutralizing mechanism, called the Mine Hammer, was designed with a prototype developed by the Agriculture and Bioresource Engineering Department, University of Saskatchewan and Defence Research and Development Canada -- Suffield. The Mine Hammer technology combined flail mechanisms and agriculture tillage interaction mechanics. The prototype was retrofitted to be powered by a 78.4 kW tractor and was field evaluated in August 2002. The test plots represented gravel road, prairie clay soil with stubble and full stand of Kochia weed for vegetation and simulated tree stump terrains. Dummy or mechanical replicas of antipersonnel landmines were placed at 0, 25, 50, 100 and 200mm depths. The Mine Hammer triggered and/or fragmented the replica landmines. Its mechanical neutralization effectiveness over the five test plots was 97%. The Mine Hammer produced a two layer overburden consisting of a loose till above a dense, compact soil layer.

The performance of simple tool shapes in terms of draft with speed of operation was evaluated in the soil bin facility of the Department of Agricultural and Bioresource Engineering, University of Saskatchewan. A hydraulic driven monorail system was developed, which was capable of speeds up to 10 m/s. The results showed that the disturbed soil remained close to the cutting path, and the elliptical shape exhibited the lowest draft increment with speed.